1. Technical Field
The present invention relates to a stereo camera system and a method for controlling convergence, and more particularly, to a stereo camera system and a method for controlling convergence capable of improving system performance such as improvement in an image implementation speed, prevention of an image breaking phenomenon, or the like, and simplifying the system, by reducing calculations for controlling convergence and applying a line memory.
2. Description of the Related Art
With the distribution of a 3D TV, producing various contents has been demanded from a consumer. To this end, a development of a stereo camera has been actively conducted.
At present, the most efficient method used in mobile devices use a binocular camera (stereo camera). However, the binocular camera has a problem in dizziness and eye fatigue due to a misalignment between convergence of a user and convergence of a camera.
In more detail, an image shown in FIG. 1 corresponds to a left image and a right image sequentially arranged in a pixel by pixel by using the binocular camera. In this case, a format type used in an autostereoscopic 3D display panel is displayed on a screen. As shown in FIG. 1, when the convergences are aligned, left and right images of central objects are the same so as to be converged to a display device, such that a user can recognize the same distance, thereby reducing dizziness and fatigue.
When the user fixes or moves to the camera to other objects, positions of the objects are changed and thus, the convergence positions of the focused objects are changed. In this case, as shown in FIG. 2, when the convergences are not calibrated, disparity of the focused object is large, such that the focused objects look like being further protruded or recessed as compared with a 3D display device. Therefore, there is a problem in that the user focusing a screen center of the display device may feel dizziness and fatigue.
In order to improve the problem, the method for calibrating convergence according to the related art as disclosed in KR Laid-Open Patent Publication No. 2007-0030501 is a method that stores both-eyes images photographed by a binocular camera in a frame memory and shifts the stored both-eyes images to the left and right to calibrate the convergence.
However, a method of moving all the images using the frame memory is a method of calculating correlation of left and right images by cropping all the both-eyes images stored and as a result, the method increases calculations to make it difficult to use real-time calibration such as photographing moving pictures, or the like, and increase used power consumption and uses a large-capacity external frame memory to increase complexity of hardware and increase a system size.